共查询到19条相似文献,搜索用时 78 毫秒
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张坚 《上海生物医学工程》2009,(2):115-118
介绍了Dr/tger麻醉机与呼吸机结构与工作原理。Fabius麻醉机潮气量不准与压力报警故障分析及排除方法;呼吸机FiO2低报警与开机后反复起动自检的故障分析及排除方法。 相似文献
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自然界中,许多动物都有天敌,但这些动物不仅没有被天敌消灭,还与它们共存了下来,逐步形成了生态平衡。可见,这些聪明的动物们都有着各自的独门秘笈——一套属于自己的防卫策略。而在这些策略中,最直接而又行之有效的方法就是报警,即一个动物会将危险通过某种通讯行为告之另一个或另一群动物。那么,动物们会采取哪些方式报警呢?是不是只有“发出叫声”这一种方式呢?它们报警是为了提醒其他同伴注意,还是为了保护自已呢?种种问题隐藏在报臀行为的背后,等待人们云发掘。 相似文献
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林海 《上海生物医学工程》2000,(3)
故障现象 每次开机,自检时出现温度报警,提示比色腔温度未到达设定值,但过半个小时后温度又能达到设定值,以后一直正常。该现象均在开机时出现。 故障分析与检查 根据该加热电路原理,比色腔为一长方体,供比色条比色。比色腔的温度是由二组晶体管发热提供。每组有二个晶体管,受控于一只热敏电阻。工作原理:开机时二组晶体管同时工作,其中一组温度高,一组温度低。高温一组是快速升温,当温度升到一定 相似文献
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目的分析不同病原菌在Bact/Alert 3D血培养仪中的阳性报警时间。方法收集浙江大学医学院附属第一医院2012年10月到2013年8月血培养阳性报警时间,分析病原菌种类,算出各常见病原菌阳性报警的中位时间。结果总共1 472份阳性标本:革兰阳性菌占55.2%,革兰阴性菌占37.5%,真菌占7.3%。对血培养阳性报警时间进行分析:≤12 h、≤24 h、≤48 h报警的病原菌分别为420株(28.5%)、956株(64.9%)、1290株(87.6%)。血培养阳性病原菌仪器报警中位时间分别为肠杆菌科细菌(10.8 h)、非发酵菌属(13.9 h)、链球菌属(14.6 h)、肠球菌属(14.5 h)、葡萄球菌属(22.3 h)、真菌(43.4 h)。大肠埃希菌(10.1 h)、鲍曼不动杆菌(10.8 h)、阴沟肠杆菌(10.8 h)、肺炎克雷伯杆菌(11.1 h)阳性报警中位时间相近,都≤12 h。结论根据全自动血培养仪对不同种类微生物阳性报警时间的差别,可初步判断病原菌的生长和类型,第一时间指导临床医师准确、合理选择抗菌药物。 相似文献
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Abnormal and excessive plantar pressure is a major risk factor for the development of foot ulcers in patients with loss of protective pain sensation. Repeated pressure with each step can result in inflammation at specific points, followed by ulcer formation. Patients with peripheral nerve disease are unable to prevent the development of such lesions, which often lead to amputation. For this reason, it has been suggested that a fundamental therapeutic intervention should be the reduction of high plantar pressure. We have developed a portable, battery-operated ambulatory foot pressure device (AFPD) which has two important functions: (1) to determine the areas of high plantar pressure, and (2) to provide an acoustic alarm, adjusted to a specific pressure load, which is triggered when weight-bearing exceeds the predetermined plantar pressure. A memory of plantar pressure parameters allows for downloading of the data and sequential analysis during the investigation period. Such an alarm device could replace the lack of pain sensation and may play an important role in the prevention of ulcer development and lower extremity amputation. 相似文献
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Chivers DP Wisenden BD Hindman CJ Michalak TA Kusch RC Kaminskyj SG Jack KL Ferrari MC Pollock RJ Halbgewachs CF Pollock MS Alemadi S James CT Savaloja RK Goater CP Corwin A Mirza RS Kiesecker JM Brown GE Adrian JC Krone PH Blaustein AR Mathis A 《Proceedings. Biological sciences / The Royal Society》2007,274(1625):2611-2619
Many fishes possess specialized epidermal cells that are ruptured by the teeth of predators, thus reliably indicating the presence of an actively foraging predator. Understanding the evolution of these cells has intrigued evolutionary ecologists because the release of these alarm chemicals is not voluntary. Here, we show that predation pressure does not influence alarm cell production in fishes. Alarm cell production is stimulated by exposure to skin-penetrating pathogens (water moulds: Saprolegnia ferax and Saprolegnia parasitica), skin-penetrating parasites (larval trematodes: Teleorchis sp. and Uvulifer sp.) and correlated with exposure to UV radiation. Suppression of the immune system with environmentally relevant levels of Cd inhibits alarm cell production of fishes challenged with Saprolegnia. These data are the first evidence that alarm substance cells have an immune function against ubiquitous environmental challenges to epidermal integrity. Our results indicate that these specialized cells arose and are maintained by natural selection owing to selfish benefits unrelated to predator-prey interactions. Cell contents released when these cells are damaged in predator attacks have secondarily acquired an ecological role as alarm cues because selection favours receivers to detect and respond adaptively to public information about predation. 相似文献
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Acoustic signals play an important role in the lives of birds. Almost all avian species produce vocal signals in a variety
of contexts either in the form of calls or songs or both. In the present study different types of vocal signals of the tropical
avian speciesPycnonotus cafer were characterized on the basis of their physical characteristics and context of production. This species used six types
of vocal signals: contact signals, roosting signals, alarm signals, twittering signals, distress signals and begging signals.
Two types of alarm signals are produced based on predation pressure. These signals are dissimilar in all physical characteristics
except for dominant frequency. Although alarm signal type I and roosting signals are phonetically similar, they have completely
different sonogram characteristics. 相似文献
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The use and construction of an automatic gas tank switching system are described. This device monitors the gas pressure in a CO2 incubator gas system and automatically switches to a reserve tank when the main supply tank is depleted. The unit contains an alarm system that signals either loss of power or gas pressure in the supply system. 相似文献
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H. E. Roy J. Baverstock K. Chamberlain J. K. Pell 《Biocontrol Science and Technology》2005,15(8):859-866
The response of pea aphids, Acyrthosiphon pisum, to aphid alarm pheromone was not modified by infection with Beauveria bassiana. Approximately 50% of uninfected and infected aphids responded to synthetic alarm pheromone. The simulated attack of aphids infected with B. bassiana did not elicit a response in uninfected aphids. Preliminary air entrainment experiments of both uninfected aphids and aphids at different stages of B. bassiana (generalist pathogen) or P. neoaphidis (obligate pathogen of aphids) demonstrated that B. bassiana infected aphids produced less alarm pheromone than uninfected aphids and, conversely, P. neoaphidis infected aphids produced more alarm pheromone than uninfected aphids. These results are discussed with particular emphasis on the different life history strategies of these two pathogens. We hypothesise that the obligate, specialist pathogen, P. neoaphidis, is under greater selection pressure to increase pathogen transmission and survival resulting in modified host behaviour, than the generalist pathogen, B. bassiana. 相似文献
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1. Winged dispersal is vital for aphids as predation pressure and host plant conditions fluctuate. 2. Ant‐tended aphids also need to disperse, but this may represent a cost for the ants, resulting in an evolutionary conflict of interest over aphid dispersal. 3. The combined effects of aphid alarm pheromone, indicating predation risk, and ant attendance on the production of winged aphids were examined in an experiment with Aphis fabae (Homoptera: Aphididae) (Scopoli 1763) aphids and Lasius niger (Formicidae: Formicinae) (Linné, 1758) ants. 4. This study is the first to investigate the joint effects of alarm pheromone and ant attendance, and also the first to detect an influence of alarm pheromone on the production of winged morphs in A. fabae. 5. After a period of 2 weeks, it was found that aphid colonies exposed to intermittent doses of alarm pheromone produced more winged individuals, whereas ant tending had the opposite effect. The effects were additive on a log scale, and ant attendance had a greater proportional influence than exposure to alarm pheromone. A tentative conclusion is that ants have gained the upper hand in an evolutionary conflict about aphid dispersal. 相似文献
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石树中 《上海生物医学工程》2008,29(1):53-54
该复苏器操作简便、安全。只要把面罩盖住新生儿口鼻,用一只手即可对手泵吸球进行加压给氧。加压过高时能排余气并发声报警,避免发生气胸,提高抢救效果。另外,该手泵吸球可一物两用,按瘪后将长嘴放人新生儿口内或鼻孔口,放松时可吸羊水等黏液。节约原材料,降低成本,大有利于新生儿窒息复苏的推广普及。 相似文献
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Ryan J. Wasserman Rachel Kramer Tim J. F. Vink P. William Froneman 《Austral ecology》2014,39(6):732-738
Sensitivity to chemical cues associated with predation threat has been well observed in many freshwater zooplankters, yet few studies have highlighted such sensitivity in eury‐ and stenohaline metazoans. We aimed to assess sensitivity to conspecific chemical alarm cues in the estuarine copepod, Paracartia longipatella. Alarm cues associated with predation have been shown to have population level effects on certain zooplanktonic species. As such, we assessed the occurrence of such effects on population dynamics of P. longipatella over a 12 day period. Using experimental in situ mesocosms, we compared P. longipatella adult, copepodite and nauplii numbers between three treatments; one inoculated with conspecific alarm cues, one containing direct predation pressure (zooplanktivorous fish), and a control treatment containing no predation threat. Trends in population abundances were similar between the direct predation and alarm cue treatments for the six days of the experiment, decreasing in abundance. During the latter half of the study, however, P. longipatella abundances in the alarm cue treatment increased, while those in the presence of direct predation continued to decrease. In the treatment absent of any predation threat, P. longipatella abundances increased consistently over time for the duration of the study. We suggest that P. longipatella are indeed sensitive to conspecific alarm cues associated with predation threat. Furthermore, we propose that prolonged exposure to conspecific alarm cues in the absence of any real threat results in a reduction in sensitive to these cues. 相似文献
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L. F. Liebes V. M. Maher P. Scherr J. J. McCormick 《In vitro cellular & developmental biology. Plant》1976,12(3):265-268
Summary The use and construction of an automatic gas tank switching system are described. This device monitors the gas pressure in
a CO2 incubator gas system and automatically switches to a reserve tank when the main supply tank is depleted. The unit contains
an alarm system that signals either a loss of power or of gas pressure in the supply system.
This research was supported by National Cancer Institute Contract No 1-CP-33226, grants CA 13058 and CA 14680 and an institutional
grant to the Michigan Cancer Foundation by the United Foundation of Greater Detroit. 相似文献